Seismic Resilience Analysis of Deep-buried Tunnels Based on Fragility Curves
(1. Department of Geotechnical Engineering, Tongji University, Shanghai 200092; 2. College of Civil Engineering and Water Resources, Qinghai University, Qinghai 810016)
Abstract：
Seismic performance of deep-buried tunnels directly affects the resilience of cities and their post-disaster recovery capability. Traditional seismic analyses mainly focus on structural strength failure, whereas resilience-based evaluation using fragility curves enables quantitative assessment of the damage probability and functional loss of tunnels under different seismic intensities, thereby supporting resilience-oriented design throughout the tunnel life cycle. In this study, a deep-buried shield tunnel in soft ground is adopted as the research object. The concrete damage constitutive model is used to represent the tunnel lining, and a two-dimensional dynamic numerical model considering soil-structure interaction is established using finite element software, incorporating different seismic characteristics. Through incremental dynamic analysis, the dynamic response of tunnel internal forces and deformations under varying seismic intensities is investigated. Based on the peak ground acceleration as the intensity measure and deformation ratio and bending moment ratio as engineering demand parameters, the seismic probabilistic demand model of the deep-buried tunnel is constructed. Subsequently, fragility curves corresponding to different seismic intensities are developed to obtain the failure probabilities under various damage states. Furthermore, by incorporating the functional recovery function of the tunnel, the seismic resilience index is quantified for different seismic hazard levels, enabling the seismic resilience assessment of deep-buried tunnels. Results indicate that the resilience index decreases with increasing seismic intensity; however, the deep-buried tunnel can still maintain a Level II or above resilience rating, demonstrating favorable seismic resilience.
HUANG Zhongkai1 WU Yiqun1 ZHANG Dongmei1 WANG Qingzhi2
.Seismic Resilience Analysis of Deep-buried Tunnels Based on Fragility Curves[J] MODERN TUNNELLING TECHNOLOGY, 2025,V62(5): 25-35
2025, Vol. 62 